Our invention relates to a headset for use in a voice communication system and, more particularly, to a headset for use in sound-attenuating earcup assemblies such as are provided for personnel employed in certain military installations having high levels of ambient noise.
There are known in the prior art sound-attenuating earcup assemblies for persons working in a high-noise environment such as the inside of an aircraft or a tank. While it is desirable that such persons be protected from the deleterious effects of the ambient noise level, it is desirable that they be in audio communication with a radio receiver or other remote signal source while at the same time being made aware of the ambient noise. In the prior art the latter is accomplished by means of local ambient sound microphones carried by the sound-attenuating earcup assemblies. Although it is generally desirable that all persons receive the same radio signal, such considerations as sound localization make it highly desirable that each person receive only the ambient sound signal produced by his own microphone. While it is possible to provide a single earphone with two signals through series resistors to provide the desired isolation, this solution necessarily results in the dissipation of large amounts of power in such resistors. Nor is a satisfactory solution provided by merely feeding the signals to different earphones of a headset, since sound localization is best accomplished by providing ambient sound signals to both earphones of the set.